Buying locally can be tempting, because at first glance you might be thinking you avoid the risk of customs confiscating your parcel and the shipping can be cheaper.
In reality, these resellers will barely be able to utilize economies of scale and just pass the shipping on to you, with an additional margin for personal profit and to offset the customs risk.
In the end these will rarely be cheaper.
Another big risk is being scammed. Since the sellers do something that's illegal in most jurisdictions, they will try to use non-refundible, anonymous payment methods, like Western Union, crypto or Paypal f&f. In case anything goes wrong they will be out of reach.
In most instances, these Instagram sellers won't be as thoroughly reviewed as major Chinese sellers.
Our recommendation is to stick to Chinese sellers that are either explicitly on our trusted sellers list or to purchase through an agent.